Air input inside a motor during drive prevents overheating while the air exchanges heat with engine cooling water in the radiator. However, the air input during drive works as resistance, accordingly, it causes energy loss. Thus, air input from outside may be shut off at the point of cooling not required by installing a grill shutter which is capable of being opened and shut selectively and an actuator for the operation of the grill shutter at the rear side of the front bumper which is front at the driving direction basis.
Meanwhile, the actuator applies a motor including both a stator and a rotator. However, such the actuator has a problem in controlling detail position and low responsiveness in response to shaking in high-speed driving. In addition, the process of interposing electric coil to a stator is complicated, thereby causing degenerating efficiency.